If you have an old analogue wall mounted thermostat with or without a wired natural, although you have control over your central heating the temperature differential band (between on & off) can be as wide as 3 or 4 degrees. This Digital thermostat has a band differential of half a degree so the house will stay at a more constant temperature and also save a small amount of money on your heating bills. Easy to install but make sure the power supply is off and there are helpful videos on You Tube regarding explanations and installation. Wish I’d have installed this product years ago.